Click on the appropriate size for the wallpaper you want. A larger image of the wallpaper will appear. Be patient, as they might take a few mintues download.

Windows 95/98/2000/XP: Right-click over the image and choose
"Set As Wallpaper."

Mac OS 8.x: Click and hold over the image, choose "Download Image to disk" (Internet Explorer) or "Save This Image As …" (Netscape). Choose a name and location for the picture. Then go to the Appearance Control Panel, and choose the "desktop" tab. Click on "Place Picture …" and choose the picture you just saved. Click on "set desktop."